"Although we have worked around the clock to address his concerns, Attorney General Barr has just informed us that he will not attend tomorrow's hearing," Nadler told reporters on Wednesday.
Moreover, Nadler said the Department of Justice notified the committee that it will not comply with their subpoena for the full unredacted Mueller report.
Nadler added that he would continue to work with Barr to reach to get access to the full copy of the Mueller report, however, if "good-faith" negotiations are not productive then he will seek a contempt citation against the attorney general.
Upon the release of a redacted version of Mueller’s report, Barr said there was no evidence that the Trump campaign conspired with Russia to interfere in the 2016 US presidential election. Barr also said Mueller’s report did conclude that Moscow tried to influence the US election, but no American was part of those efforts.
Russia has repeatedly refuted any claims of interference in the US political system, saying the allegations were made up to excuse the election loss of Trump's opponent as well as deflect public attention from actual instances of election fraud and corruption.